Table 1:
Sample description of 2220 participants, which completed at least one assessment of discounting and alcohol use. 1084 participants were male. Please note that we have missing MCQ data from wave 1 for 18 participants due to incomplete online questionnaires.
| Wave 1 | Wave 2 | Wave 3 | Wave 4 | |
|---|---|---|---|---|
| N | 2202 | 1669 | 1489 | 1350 |
| Age | 14.4 (0.43) | 16.5 (0.63) | 19.0 (0.75) | 22.6 (0.67) |
| MCQ k (sd) | −4.35 (1.46) | −4.42 (1.41) | −4.44 (1.43) | −4.66 (1.51) |
| AUDIT total score (sd) | 1.5 (2.50) | 3.7 (3.48) | 5.6 (4.19) | 6.1 (4.64) |
| Gram alcohol / week (TLFB) | 3.8 (15.66) | -* | 89.8 (12.64) | 95.9 (105.22) |
| Number of cigarettes / week (TLFB) | 2.6 (2.65)*** | -* | 29 (35.3) | 31 (38.9) |
| Number of days with cannabis use / week (TLFB) | 0.91 (1.626) | -* | 0.34 (1.187) | 0.48 (1.483) |
| Verbal comprehension** | 108 (14.6) | − | − | − |
| Perceptual reasoning** | 97 (17.0) | − | − | − |
| Socioeconomic status | 19 (3.8) |
Note: MCQ – Monetary Choice Questionnaire; AUDIT – Alcohol Use Disorder Identification Test; TLFB – Timeline Follow Back interview
*:
TLFB data was not acquired in large IMAGEN sample at age 16
**:
IQ index scores computed from Wechsler Intelligence Scale for children
***:
Number of days with tobacco use (number of cigarettes not acquired)